Chapter 08 – Banda Oriental and Patagonia

This is a fairly long chapter, and much of it is a journal, from commentary on religious tolerance to the scientific education of the population (there are locals who express astonishment to learn that the world is round). And, then, suddenly, in the last couple of pages, we’re suddenly hit with biogeography, natural history, and the economy of nature. But more on that when we get there.

Having been delayed by the rebellion in Las Conchas for some time, Darwin rides to catch the Beagle before it leaves Monte Video. When he gets there, however, he discovers that the Beagle isn’t sailing for a couple of weeks, and so decides to travel across the plains of Patagonia.

A local breed of cattle, called the niata, differ from normal cattle. There’s an inkling of natural selection here: common cattle are able to browse on trees, but the niata are less able – and so die sooner during a drought. Darwin comments that this sort of thing has implications on the extinction of species – it is determined often by irregular, but nonetheless natural, events.

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Chapter 7 – Buenos Aires and St Fé

First off, the other day I mentioned that I would say something about my honour’s work sooner or later. I will, and, considering how excited I am about the upcoming Paul Nelson day, I’ll post something about it tomorrow*.

This is also a pretty significant chapter: there is a tremendous discussion of the biogeography of both extant and extinct species, and several instances of what are probably sexual selection, though the utility is in neither case apparent to Darwin.

Darwin first discusses bizcacha a rodent similar to an agouti. Bizcachas have never been seen east of the Uruguay River, even though the vegetation there would be well suited to their tastes. They have a habit of gathering hard objects and placing them near their burrows, but not in a way that might be employed for self-defense. He compares this to an Australian bowerbird, Chlamydera maculata. The purpose of even the bowerbird’s collections have not yet been identified: “…the Calodera maculata, which makes an elegant vaulted passage of twigs for playing in, and which collects near the spot, land and sea shells, bones and the feathers of birds, especially brightly coloured ones.” Darwin does not attempt to speculate as to the bizcacha’s purpose in accumulating these objects. The locals in both locations will, when they lose some item, will begin their searches near the nests of these creatures – often quite successfully.
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